Yarn feeding means for knitting machines



Dec. 22, 1959 A. SHORTLAND YARN FEEDING MEANS FOR KNITTING MACHINES 3'Sheets-Sheet 1 Filed Sept. 10, 1956 1 2 m n, w N f U Dec. 22, 1959 A.SHORTLAND 2,917,914

YARN FEEDING MEANS FOR KNITTING MACHINES Filed Sept. 10, 1956 3Sheets-Sheet 2 Dec. 22, 1959 A. GSHORTLAND 2,917,914

YARN FEEDING MEANS FOR KNITTING MACHINES Filed Sept. 10, 1956 3ShGGfS-Shflt 3 JLJ LJLJL "42 ugw United States YARN, FEEDING MEANS FORKNITTING MACHINES Claims priority, application Great Britain September19, 1955 '5 Claims. (Cl. 66132) This invention relates to yarn feedingmeans for knitting machines, and has for -its object to provide agenerally improved, compact and efficient form of unitary mechanism forthis purpose which is readily adjustable to vary the speed of the yarnor yarns being fed, according to knitting requirements, and is capableof simultaneously feeding a plurality of yarns to separate feeders.

The term yarn used in this specification is intended to cover a yarn orthread of any appropriate character.

The mechanism provided by this invention comprises, in combination, arotary yarn feeding component (hereinafter for convenience referred toas a drum) which has a yieldable slip-resisting surface, and meanswhereby the said drum can be driven at a uniform, but readily variable,speed related to the speed of the knitting machine upon which themechanism is mounted.

The improved mechanism may advantageously include, for the guidance ofeach relevant yarn to be fed to needles of the machine, a pair of yarnguides angularly spaced apart about and near to the cylindrical surfaceof the yarn feeding drum, the arrangement being such that a yarnproperly threaded through both guides extends partially around the saiddrum en route from a yarn supply to the needles. Thus, the yieldableslip-resisting surface of the drum frictionally engages the yarn in amore or less positive manner and drives it forward at a linear speedcorresponding to, or at least commensurate with, the rotational speed ofthe drum. It is the intention that each yarn shall normally be lappedaround approximately half or a little more of the circumference of thedrum, although provision is preferably made for varying the extent 'ofthis lap, by a relative adjustment of the yarn guides of each pairtowards or away from one another] Such a variation in thecircumferential extent of the contact with the drum results in the yarnbeing driven more or less powerfully, according to requirements. In thisway any slackness, or excessive tension, in a running yarn can beobviated.

The surface of the yarn feeding drum may be covered or treated with anyappropriate yieldable slipresisting material.

The yarn feeding drum may advantageously be made of a relatively lightmaterial, and the length thereof will be determined by the maximumnumber of yarns intended to be fed thereby. In this regard it ispossible simultaneously to feed by the same drum as'many as, say, eightyarns to a corresponding number of individual feeders. In such'a casethe drum has associated therewith as many pairs of yarn guides as thereare yarns in the full complement of yarns to be fed, and these pairs areequally spaced'apart axially, i.e. along the drum. With such mechanismin use, not only can the yarn guides of the several pairs be relativelyadjusted simultaneously, but any variation in the speed of rotation ofthe yarn feeding drum affects all of the yarns to the same extent. Thatis to say, by a single adjustment of the drum driving means, the linearspeed of all the yarns being fed by the drum will be simultaneouslyvaried the same amount.

2,917,914 Patented Dec. 22, 1959 The rotary drum may advantageously befrictionally driven from any appropriate rotating part of the knittingmachine, through the medium of suitable gearing, provision being madefor practically infinite variation, between limits, of the rotationalspeed of the drum.

In a convenient embodiment of the invention, a friction driving wheel,arranged with its periphery in contact with a plane face at one end ofthe drum, is rotatable together with a spindle adapted to be driven at asubstantially uniform predetermined speed from a rotating part of themachine, this driving wheel being adjustable axially suchwise as to varythe radial distance between it and the axis of the drum. Consequently,by setting the friction driving wheel nearer to the axis of the drumthespeed of the latter will be increased, and, vice versa. The hub of thedriving wheel may conveniently be slidable axially along the drivenspindle, axial movements being imparted to the said hub for the purposeof adjusting the friction driving wheel by manually operable screw orequivalent means.

In order that the invention may be more clearly understood and readilycarried into practical effect, a specific constructional form of theimproved yarn feeding unit suitable for application to a multi-feedcircular knitting machine of the cylinder and dial type and embodyingthe foregoing and other features of the invention will now be described,by way of example, with reference to the accompanying drawings, wherein,

Figure 1 .is a general perspective view of the said yarn feeding unit, I

Figure 2 is an end view of the same as seen in the direction of thearrow A in Figure 1,

Figure 3 is a vertical sectional view taken on the line 111111 of Figure2, and

Figure 4 is a detail sectional view illustrating a smaller yarn feedingdrum fitted upon the unit.

Like parts are designated by similar reference characters throughout thedrawings.

In the illustrated example, the yarn feeding drum 1 consists of alightcylinder of aluminum a little over 5" in length and having an externaldiameter of approximately 2%. The circumferential surface of the drums 1is wholly covered with a uniformly thick covering of silicon rubber 2. Acovering of silicon rubber is found to be eminently satisfactory for theintended purpose. Although such rubber exercises the required degree ofgrip on a yarn, such as that indicated at Y in each of Fig ures 1 and 2,a covering of this particular material is nevertheless of such a natureas to give to an extent sufficient to prevent a broken yarn fromwrapping around the drum 1. The inner end of the light cylinderconstituting the drum 1 is closed by a circular end plate or disc 3presenting a plane outer surface 351 (see Figure 3) for contact with asmall friction driving wheel 4 hereinafter to be described. The diameterof the end plate or disc 3 is the same as the external diameter of thealuminium cylinder, and the inner side of the said plate or disc isformed with a central boss 5 to enable it to'be fitted upon and to berigidly secured to the inner end of a rotary tube 6 which, as depictedin Figure 3, is concentric with and constitutes a hub-like carrier forthe cylindrical drum 1. The tube 6 is mounted to rotate freely about ahorizontal spindle 7 which at its inner end is secured, by means of agrub screw 8, within a bored boss 9'ex'tending outwardly from the mainbracket 10 of the unit. The inner end of therotary tube 6 is suitablycounterbored at 621 to receive a bush 11 which is arranged to turn aboutthe boss 9 and, at its inner end, is formed to receive a plain bearing'12. -In a similar way, the

outer end of the tube 6 is counter-bored at 6b to receive a bearing bush13 in which is fitted another'pla'in bearing'ltl. The plain bearings 12and 14 may, if desired, be

replaced by anti-friction bearings of the needle or roller type. Thecentral tube 6 is spring loaded, suchwise as to hold the outer planeface 3a of the end plate or disc 3 firmly in contact with the frictiondriving wheel 4, by means of a compression spring 15. As will be seen inFigure 3, the spring surrounds the outer end portion of the horizontalspindle 7 and is interposed between an abutment, e.g. a washer 16, onthe latter andan end thrust anti-friction bearing 17 located, as shown,adjacent to the outer end of the bush 13. The outer end of the drum 1 isclosed by a cap 18 which is centrally bossed at 18a to fit upon theconcentric tube 6 and is also provided at its periphery with an inwardlydirected annular flange 18b which is engaged within a counterbore in thedrum 1. A somewhat similarly flanged and centrally bosseddrum-supporting plate 19 is fitted with in the yarn feeding drum 1intermediate its ends. To receive the said plate 19 the drum iscounterbored at its inner end so as to provide an annular shoulder 20against which the plate can be located. The entire drum 1, complete withits end cap 13 and supporting plate 19, is adapted to be engaged, as aunit, with the'central rotary tube 6 by an axial sliding movement. Whenfully engaged with the tube 6 by pushing it up to the inner face .of thecircular end plate or disc 3, the drum 1 is secured to the said tubee.g. by means of a radially extending screw 21. Thus, by withdrawingthis screw, the drum 1 can be readily removed from the tube 6, asoccasion may demand.

The friction driving wheel 4, which may advantageously be made of nylonor any appropriate rubber or rubber-like composition, is mounted upon ahub 22 which is rotatable together with, but is slidable axially up anddown, a vertical spindle 23 extending at right angles to the drum axisa. The spindle 23 is mounted for rotation in any suitable anti-frictionbearings 24 and 25 provided in the main bracket 10. The lower end of thevertical spindle 23 has secured thereto a pinion 26 which, when the unitis mounted upon a knitting machine of the cyl inder and dial type, isarranged in mesh with a gear ring 27, secured upon a gear 28 (Figures 2and 3) arranged to be driven from the dial. For the purpose of movingthe hub 22 up and down the spindle 23 there is provided a rotatablevertical screw 29 with which cooperates a nut 30 having integraltherewith a radially extending finger 31 the outer end of which isengaged in a circumferential groove 32 formed in the said hub. The screw29 thus extends parallel to the spindle 23 and is mounted to turn invertically aligned bearing holes formed respectively in the upper andlower portions of the bracket 10. The screw 29 is prevented from anyaxial move ment so that, when it is rotated in one direction, the nut 30will be caused to travel upwards and when the screw is rotated in thereverse direction the said nut will travel downwards. Accordingly,although the nylon, rubber or like friction driving wheel 4 is drivenfrom the machine at a uniform speed, the rotational speed of the yarnfeeding drum can be readily varied, within limits and according torequirements, by effecting an axial adjustment of the nut 30, such anadjustment serving to vary the radial distance between the drum axis aand the point of contact of the wheel 4 with the driven circular endplate or disc 3. Thus, with the wheel 4 in the full line positionindicated in Figure 3, the drum 1 rotates at its highest speed, whereaswith the said wheel in the chainline position the lowest drum speed isobtained.

For effecting rotation of the screw 29 manually, and hence also manualadjustment of the nut 30 as required, there is provided a peripherallymilled knob 31 which is rigidly secured to the screw, near the lower endthereof, and a portion of which is arranged to protrude through anaperture 32 formed in the back of a hollow part of the bracket 10. Meansof any suitable character may be provided to secure the knob 31 againstrotation after an adjustment. If desired, moreover, the periphery of avernier setting dial 33 combined with the knob 31 may be appropriatelycalibrated for use in conjunction with a fixed index on the bracket.

In an alternative constrution, not shown, the friction driving disc maybe rigidly secured to the vertical spindle, in which instance the latteritself may be adjustable up and down and the gear 28 may be madesufliciently thick to ensure maintenance of driving engagement betweenthe said gear and the pinion 26 during adjustments. For instance, thevertical spindle may conveniently be mounted for rotation in an axiallymovable non-rotatable bush to which axial movements can be readilyimparted by manually operable rack and pinion or equivalent means.

To provide a different range of drum speeds, the pinion 26 at the lowerend of the driving wheel spindle 23 may be interchangeable with anotherhaving a different number of teeth. To enable such an interchange to beeffected, the main bracket 10 may be made to swing in and out upon itssupport 34 on the machine, e.g. about the axis of a pivot screw 35.After a fresh pinion has been intermeshed with the gear ring 27, byturning the bracket 10 inwards about the pivot screw 35, the unit may beeasily secured in position by re-tightening the said screw. In thespecific example illustrated the support 34 is constituted by a guardfor the gear ring 27 and gear 28.

On a supplementary bracket 36 attached to the main bracket 19 of theunit is adjustably secured the inner end of a fixed horizontal bar 37which, as shown in Figure 1, is drilled at regular intervals therealongto re ceive a longitudinal series of uniformly spaced yarn guiding eyes38 or equivalent. This bar 37, which is disposed near to and parallelwith the surface of the yarn feeding drum 1, is of approximately thesame length as the latter. As will be seen, the inner end 37a of the bar37 is slotted to permit of adjustment of the bar up or down Within thelimits of the slot. Another similar adjustable bar 39, furnished witheyes 40 respectively disposed in line with the corresponding eyes 38 ofthe bar 37 is mounted adjacent to the drum on an extension 36a of thesupplementary bracket 36. The yarn guide bars 37 and 39 are accordinglyadjustable one or each in relation to the other suchwise as to vary thecircumferential extent of the contact of the feeding yarns, such as Y,with the drum 1. That is to say, by appropriate relative adjustment ofthe bars 37 and 39, the extent of the top of the yarns around thecircumference of the drum 1 can be varied, according to knittingrequirements.

To enable different yarns to be fed at respectively different speeds inone and the same machine, several alternative expedients may be adopted.For instance, two or more of the cylindrical yarn feeding drums may befitted onto the machine and arranged to be driven from a common rotatingpart of the latter, provision in this case being made for varying therotational speeds of the drums individually.

Different ranges of speeds can also be obtained by exchanging acylindrical drum for another of a different diameter, utilising the samecircular end plate or disc 3. Thus, for example, and comparing Figure 3with Figure 4, it will be appreciated thatthe drum 1 may be removed fromthe central rotary tube 6 and replaced by another drum 1 of asubstantially smaller diameter. In the case of the small drum there isno need to provide an intermediate drum-supporting plate since the innerend of the drum 1' can, as shown in Figure 4, be supported directly uponthe boss 5 of the circular end plate or disc 3. The outer end of thesaid small drum 1' is closed by a cap 18' which is also made to fit uponthe tube 6. A screw 41 is employed to secure the drum 1 to the rotarytube. Accordingly, in one and the same machine, yarn feeding unitsfitted with drums of respectively different diameters may be used.

Again, if one and the same cylindrical yarn feeding drum is covered ortreated with adjoining bands of contrastlng materials which areslip-resisting to respectively different degrees, yarns lapped aroundthe drum and engaged with the different bands will be fed at differentspeeds.

A similar result could be achieved by providing upon one and the samedrum adjoining slip-resisting bands of clrcumferential portions ofslightly varying external diameters. Such bands or portions may befitted upon or combined with a sleeve which is secured upon thecylindrical drum. Or, for the same purpose narrow drums of varyingdiameters may be combined together to provide a unitary rotarycomponent.

Again, to feed different yarns at different speeds, the circumferentialextents of the contact of the yarns with one and the same drum may becommensurately different.

At 42 in Figure 2 is indicated a stop motion device equipped with apivoted wire dropper 43 arranged to be engaged and normally held up inthe full line position shown by the yarn Y. If the yarn breaks or runsout, the dropper 43 falls to the chain line position to initiatestoppage of the knitting machine. A series of such stop motion devicesis indicated in chain lines in Figure 3.

At 44 is shown an adjustable rod by which yarns running from the drum 1to the stop motion devices 42 are supported. This rod may convenientlybe made of steel and covered with glass.

In lieu of a cylindrical drum, there may be provided a rotary yarnfeeding component composed of a plurality of co-axial and adjoiningsections each of truncated conical form.

It is also within the scope of the invention to provide two drum unitsof different diameters and to drive these simultaneously at the samespeed from a common drive source: in this case the said drum units mayconveniently be arranged one above the other pick-a-back fashion.

I claim:

1. In a knitting machine, a yarn feeding mechanism comprising, incombination, a rotary yarn feeding drum of open cylindrical form, twoparallel spaced longitudinal rows of yarn guides extending axiallyalongside the drum near to the cylindrical surface thereof, said guidesbeing arranged in axially spaced pairs and each of said pairs enablingan individual running yarn appropriately threaded therethrough to extendpartially around the drum in contact therewith whereby the drum can feedsimultaneously as many yarns as there are pairs of guides, said drumhaving a covering of a slip-resisting material which is adapted toexercise a grip on yarns guided around the drum as aforesaid and yet iscapable of yielding to an extent suflicient to prevent a broken yarnfrom wrapping around said drum, a carrier for said drum concentricallyrotatable and in an interior engagement with said drum, a member forminga closure for one end of said drum and rotatable with said drum throughengagement with said carrier, said member presenting a plain outer face,a friction driving wheel arranged with its periphery in contact withsaid outer face, a spindle, means driving said spindle at a uniformspeed related to the speed of the knitting machine, the hub of thedriving Wheel keyed to but slidable axially along said driven spindle, amanually adjustable screw provided for effecting the axial movement ofthe driving wheel hub, said driving wheel hub having a circumferentialgroove therein, a nut arranged to cooperate with said screw, and anelement projecting from said nut and engaged in said groove.

2. In a knitting machine, a yarn feeding mechanism according to claim 1having a bracket carrying the said mechanism, wherein said spindledriving means includes a pinion secured to said spindle and a rotarygear member meshing with said pinion and driven at a uniform speed fromthe knitting machine, said bracket being movable upon a support in sucha manner as to enable interchanging said pinion on said driven spindlewith another pinion having a different number of teeth so as to providea different range of drum speeds.

3. A yarn feeding mechanism according to claim 1 having a spindle aroundwhich said carrier is arranged to revolve and an abutment provided onsaid spindle, wherein said carrier is loaded axially by a springinterposed between it and said abutment suchwise as to maintain theplain outer face of said plain-outer-faced member in contact with thefriction driving wheel.

4. A yarn feeding mechanism according to claim 1, wherein theslip-resisting material covering said drum is a silicone rubber.

5. Ayarn feeding mechanism according to claim 1,. including a mainbracket, aligned bearings in said bracket on which the driven spindle ismounted to rotate, a supplementa'ry bracket attached to said mainbracket, and a pair of straight parallel bars mounted upon said supple--mentary bracket, said bars having set therein rows of yarn guides in theform of apertured elements and being adjustable towards and away fromone another in directions perpendicular to their length.

References Cited in the file of this patent UNITED STATES PATENTS

